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1.
A pharmacognostic study of aerial parts of Scutellaria baicalensis Georgi (Lamiaceae family) has been carried out. A merchandising analysis has been performed to determine the basic quality parameters of S. baicalensis. A chemical composition analysis has revealed the presence of organic acids, free carbohydrates, polysaccharides, amino acids, alkaloids, flavonoids, phenolic acids, anthocyanins, tannins, photosynthetic pigments, lipids, and triterpene compounds. Ethyl acetate and ethanol fractions, extracted from the aerial parts of S. baikalensis, have shown a significant antiradical activity.  相似文献   

2.
Using different explants of in vitro seed grown Scutellaria baicalensis Georgi plantlets, hairy roots were induced following inoculation of Agrobacterium rhizogenes strains A4GUS, R1000 LBA 9402 and ATCC11325. The A4GUS proved to be more competent than other strains and the highest transformation rates were observed in cotyledonary leaf explant (42.6 %). The transformed roots appeared after 15–20 d of incubation on hormone free Murashige and Skoog medium. Growth of hairy roots was assessed on the basis of total root elongation, lateral root density and biomass accumulation. Maximum growth rate was recorded in root:medium ratio 1:100 (m/v). Hairy root lines were further established in Gamborg B5 medium and the biomass increase was maximum from 15 to 30 d. PCR, Southern hybridization and RT-PCR confirmed integration and expression of left and right termini-linked Ri T-DNA fragment of the Ri plasmid from A4GUS into the genome of Scutellaria baicalensis hairy roots. GUS assay was also performed for further integration and expression. All the clones showed higher growth rate them non-transformed root and accumulated considerable amounts of the root-specific flavonoids. Baicalin content was 14.1–30.0 % of dry root mass which was significantly higher then that of control field grown roots (18 %). The wogonin content varies from 0.08 to 0.18 % among the hairy root clones which was also higher than in non-transformed roots (0.07 %).  相似文献   

3.
In vitro manipulation of plant regeneration in the Chinese medicinal species Scutellaria baicalensis Georgi (Huang-qin) resulted in 26 chemically distinct germplasm lines. Antioxidant potential, growth rate and concentration of baicalin, baicalein, melatonin, and wogonin were the selective markers used to identify elite lines. Metabolomic analysis of a subset of the most distinct lines revealed that Huang-qin extracts contained over 2,000 compounds including 781 determined to be of putative medicinal importance as determined by a database search, as well as previously unidentified amino-derivatives of baicalin and wogonin. Huang-qin also contained a metabolite with the same net formula as hyperforin, previously thought to be unique to Hypericum perforatum L. Together these results provide new insights into the biochemical complexity of an important medicinal species and demonstrate the power of in vitro manipulation in combination with untargeted metabolomic screening for the production of new germplasm.  相似文献   

4.
Information on the phenolic compounds from the Baikal scullap Scutellaria baicalensis Georgi, family Lamiaceae, is given. Structures of 125 compounds are presented, and information is given on their distribution in the aboveground and belowground parts of the plant and in the tissue culture of the root. There are generalized data on the use of TLC and HPLC methods for the separation of the main components of Scutellaria baicalensis.  相似文献   

5.
Summary  Two new combinations, one new and one resurrected name in Plectranthus L’Hér. are provided for species formerly placed in Leocus A. Chev.; conservation assessments are made for five species.  相似文献   

6.
Two repeated DNA sequences isolated from a partial genomic DNA library of Helianthus annuus, p HaS13 and p HaS211, were shown to represent portions of the int gene of a Ty3 /gypsy retroelement and of the RNase-Hgene of a Ty1 /copia retroelement, respectively. Southern blotting patterns obtained by hybridizing the two probes to BglII- or DraI-digested genomic DNA from different Helianthus species showed p HaS13 and p HaS211 were parts of dispersed repeats at least 8 and 7 kb in length, respectively, that were conserved in all species studied. Comparable hybridization patterns were obtained in all species with p HaS13. By contrast, the patterns obtained by hybridizing p HaS211 clearly differentiated annual species from perennials. The frequencies of p HaS13- and p HaS211-related sequences in different species were 4.3x10(4)-1.3x10(5) copies and 9.9x10(2)-8.1x10(3) copies per picogram of DNA, respectively. The frequency of p HaS13-related sequences varied widely within annual species, while no significant difference was observed among perennial species. Conversely, the frequency variation of p HaS211-related sequences was as large within annual species as within perennials. Sequences of both families were found to be dispersed along the length of all chromosomes in all species studied. However, Ty3 /gypsy-like sequences were localized preferentially at the centromeric regions, whereas Ty1/ copia-like sequences were less represented or absent around the centromeres and plentiful at the chromosome ends. These findings suggest that the two sequence families played a role in Helianthusgenome evolution and species divergence, evolved independently in the same genomic backgrounds and in annual or perennial species, and acquired different possible functions in the host genomes.  相似文献   

7.
New combinations are proposed in anticipation of the Polygonaceae treatment in the forthcoming volume of Intermountain Flora: Polygonum kelloggii var. esotericum, P. kelloggii var. watsonii , Rumex densiflorus var. pycnanthus , R. salicifolius var. utahensis, and R. occidentalis var. tomentellus. Typifications are proposed to facilitate ongoing studies in Polygonaceae and to maintain current usage.  相似文献   

8.
9.
Single (unpaired) vegetative cells of freshwater pennate diatom Neidium cf. ampliatum differentiated into gametangia and produced a single zygote (auxospore) via a pedogamic process. The gametic nuclei fused after auxospore expansion had begun. The auxospore expanded in parallel to the apical axis of the gametangium.  相似文献   

10.
A species-level review of the genus Clinopodium in Bolivia is presented. Characters used to distinguish taxa are discussed and evaluated with emphasis being given to nutlet characteristics for the first time. Nine species are described, seven from Bolivia, one of which, C. pilosum J. R. I. Wood is described as new. Bystropogon uniflorus Rusby ex Briq. is treated as subsp. uniflorum (Rusby ex Briq.) J. R. I. Wood of C. axillare (Rusby) Harley and its typification is discussed. Three subspecies of C. bolivianum are recognised, one of which subsp. diffusum J. R. I. Wood is described as new. Notes on salient characteristics of each taxon, on intermediate forms and on the distribution of each species are provided, as well as a key to species, maps and illustrations.  相似文献   

11.
We have investigated the floral ontogeny of Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis (of the eucalypt group, Myrtaceae) using scanning electron microscopy and light microscopy. Several critical characters for establishing relationships between these genera and to the eucalypts have been determined. The absence of compound petaline primordia in Arillastrum, Allosyncarpia, Stockwellia and Eucalyptopsis excludes these taxa from the eucalypt clade. Post-anthesis circumscissile abscission of the hypanthium above the ovary in Stockwellia, Eucalyptopsis and Allosyncarpia is evidence that these three taxa form a monophyletic group; undifferentiated perianth parts and elongated fusiform buds are characters that unite Stockwellia and Eucalyptopsis as sister taxa. No floral characters clearly associate Arillastrum with either the eucalypt clade or the clade of Stockwellia, Eucalyptopsis and Allosyncarpia.We gratefully acknowledge Clyde Dunlop and Bob Harwood (Northern Territory Herbarium) for collecting specimens of Allosyncarpia, and Bruce Gray (Atherton) for collecting specimens of Stockwellia. The Australian National Herbarium (CANB) kindly lent herbarium specimens of Eucalyptopsis for examination. This research was supported by a University of Melbourne Research Development Grant to Andrew Drinnan.  相似文献   

12.
A revision of Penstemon sect. Saccanthera subsect. Serrulati includes a new species (P. salmonensis), a new variety (P. triphyllus var. infernalis), and the elevation of a subspecies to species (P. curtiflorus), bringing the total number of species to eight, which are keyed and described, complete with nomenclature and type citations.  相似文献   

13.
Traditionally viewed as an Andean grain crop,Chenopodium quinoa Willd. includes domesticated populations that are not Andean, and Andean populations that are not domesticated. Comparative analysis of leaf morphology and allozyme frequencies have demonstrated that Andean populations, both domesticated(quinua) and free-living(ajara), represent an exceptionally homogeneous unit that is well differentiated from allied domesticates of coastal Chile(quingua) and freeliving populations of the Argentine lowlands(C. hircinum). This pattern of relationships indicates that Andean populations represent a monophyletic crop/weed system that has possibly developed through cyclic differentiation (natural vs. human selection) and introgressive hybridization. Relative levels of variation suggest that this complex originated in the southern Andes, possibly from wild types allied withC. hircinum, with subsequent dispersal north to Colombia and south to the Chilean coast. Coastal populations were apparently isolated from post-dispersal differentiation and homogenization that occurred in the Andes. Other data point toward a center of origin in the northern Andes with secondary centers of genetic diversity subsequently developing in the southern Andes and the plains of Argentina. Comparative linkage of South American taxa, all tetraploid, with North American tetraploids of the subsection will eventually clarify this problem. While the possibility of a direct phyletic connection betweenC. quinoa and the Mexican domesticate(C. berlandieri subsp. nuttalliae,) cannot be excluded, available evidence indicates that the latter represents an autonomous lineage that is associated with the basal tetraploid, C. b. subsp.berlandieri, through var.sinuatum, whereas South American taxa show possible affinities to either var. zschackei or var.berlandieri. An extinct domesticate of eastern North America,C. b. subsp.jonesianum, represents either another instance of independent domestication, possibly from subsp. b. var.zschackei, or a northeastern outlier of subsp.nuttalliae.  相似文献   

14.

Background

Gonadotropin releasing hormone (GnRH) is responsible for stimulation of gonadotropic hormone (GtH) in the hypothalamus-pituitary-gonadal axis (HPG). The regulatory mechanisms responsible for brain specificity make the promoter attractive for in silico analysis and reporter gene studies in zebrafish (Danio rerio).

Results

We have characterized a zebrafish [Trp7, Leu8] or salmon (s) GnRH variant, gnrh 3. The gene includes a 1.6 Kb upstream regulatory region and displays the conserved structure of 4 exons and 3 introns, as seen in other species. An in silico defined enhancer at -976 in the zebrafish promoter, containing adjacent binding sites for Oct-1, CREB and Sp1, was predicted in 2 mammalian and 5 teleost GnRH promoters. Reporter gene studies confirmed the importance of this enhancer for cell specific expression in zebrafish. Interestingly the promoter of human GnRH-I, known as mammalian GnRH (mGnRH), was shown capable of driving cell specific reporter gene expression in transgenic zebrafish.

Conclusions

The characterized zebrafish Gnrh3 decapeptide exhibits complete homology to the Atlantic salmon (Salmo salar) GnRH-III variant. In silico analysis of mammalian and teleost GnRH promoters revealed a conserved enhancer possessing binding sites for Oct-1, CREB and Sp1. Transgenic and transient reporter gene expression in zebrafish larvae, confirmed the importance of the in silico defined zebrafish enhancer at -976. The capability of the human GnRH-I promoter of directing cell specific reporter gene expression in zebrafish supports orthology between GnRH-I and GnRH-III.
  相似文献   

15.
A genetic transformation system has been developed for callus cells of Crataegus aronia using Agrobacterium tumefaciens. Callus culture was established from internodal stem segments incubated on Murashige and Skoog (MS) medium supplemented with 5 mg l−1 Indole-3-butyric acid (IBA) and 0.5 mg l−1 6-benzyladenine (BA). In order to optimize the callus culture system with respect to callus growth and coloration, different types and concentrations of plant growth regulators were tested. Results indicated that the best average fresh weight of red colored callus was obtained on MS medium supplemented with 2 mg l−1 2,4-dichlorophenoxyacetic acid (2,4-D) and 1.5 mg l−1 kinetin (Kin) (callus maintenance medium). Callus cells were co-cultivated with Agrobacterium harboring the binary plasmid pCAMBIA1302 carrying the mgfp5 and hygromycin phosphotransferase (hptII) genes conferring green fluorescent protein (GFP) activity and hygromycin resistance, respectively. Putative transgenic calli were obtained 4 weeks after incubation of the co-cultivated explants onto maintenance medium supplemented with 50 mg l−1 hygromycin. Molecular analysis confirmed the integration of the transgenes in transformed callus. To our knowledge, this is the first time to report an Agrobacterium-mediated transformation system in Crataegus aronia.  相似文献   

16.
Studying Pneumocystis has proven to be a challenge from the perspective of propagating a significant amount of the pathogen in a facile manner. The study of several fungal pathogens has been aided by the use of invertebrate model hosts. Our efforts to infect the invertebrate larvae Galleria mellonella with Pneumocystis proved futile since P. murina neither caused disease nor was able to proliferate within G. mellonella. It did, however, show that the pathogen could be rapidly cleared from the host.  相似文献   

17.
Callicarpenal (13, 14, 15, 16-tetranor-3-cleroden-12-al) and intermedeol [(4S,5S,7R,10S)-eudesm-11-en-4-ol], isolated from American beautyberry, Callicarpa americana (Lamiaceae), were evaluated in laboratory bioassays for repellent activity against host-seeking nymphs of the blacklegged tick, Ixodes scapularis, and lone star tick, Amblyomma americanum. A strip of organdy cloth treated with test solution was doubly wrapped (treatment on outer layer) around the middle phalanx of a forefinger and ticks released on the fingertip. Callicarpenal and intermedeol, at 155 nmole/cm2 cloth repelled 98 and 96% of I. scapularis nymphs, respectively. Dose response tests with I. scapularis nymphs showed no difference in repellency among callicarpenal, intermedeol and Deet (N,N-diethyl-3-methylbenzamide), however, SS220 ((1S,2′S)-2-methylpiperidinyl-3-cyclohexene-1-carboxamide) was significantly more repellent than the other compounds. Callicarpenal, at 155 nmole/cm2 cloth, repelled 100 and 53.3% of I. scapularis nymphs at 3 and 4 h, respectively, after the cloth was treated, whereas intermedeol repelled 72.5% of I. scapularis nymphs 3 h after treatment. In comparison with the results obtained with I. scapularis, callicarpenal, intermedeol, Deet and SS220 were less effective against A. americanum. Only intermedeol and SS220 repelled significantly more A. americanum than ethanol controls at 155 nmole compound/cm2 cloth. At 1,240 nmole/cm2 cloth, callicarpenal and intermedeol repelled 20 and 40% of A. americanum nymphs.  相似文献   

18.
19.
20.
Lin X  Minamisawa N  Takechi K  Zhang W  Sato H  Takio S  Tsukaya H  Takano H 《Planta》2008,228(4):601-608
ANGUSTIFOLIA (AN), a plant homolog of C-terminal binding protein, controls the polar elongation of leaf cells and the trichome-branching pattern in Arabidopsis thaliana. In the present study, degenerate PCR was used to isolate an ortholog of AN, referred to as LgAN, from larch (Larix gmelinii). The LgAN cDNA is predicted to encode a protein of 646 amino acids that shows striking sequence similarity to AN proteins from other plants. The predicted amino acid sequence has a conserved NAD-dependent 2-hydroxy acid dehydrogenase (D2-HDH) motif and a plant AN-specific LxCxE/D motif at its N-terminus, as well as a plant-specific long C-terminal region. The LgAN gene is a single-copy gene that is expressed in all larch tissues. Expression of the LgAN cDNA rescued the leaf width and trichome-branching pattern defects in the angustifolia-1 (an-1) mutant of Arabidopsis, showing that the LgAN gene has effects complementary to those of AN. These results suggest that the LgAN gene has the same function as the AN gene.  相似文献   

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